Epidiaphyseal versus other intercalary allografts for tumors of the lower limb

Graft Infections in Biologic Reconstructions in the Oncologic Setting: A Systematic Review of the Literature

Background: Biologic graft infection (BGI) is one of the main complications in graft reconstructions. However, very little evidence exists regarding the epidemiology of BGI, as most of the data come from sparse reports. Moreover, most of the series did not detail the treatment and outcome of graft infections. The aim of this systematic review of the literature is to provide a comprehensive data collection on BGI after oncologic resections. Methods: Three different databases (PubMed, Scopus, and Web of Science) were searched for relevant articles, and further references were obtained by cross-referencing. Results: 139 studies met the inclusion criteria. A total of 9824 grafts were retrieved. Among these, 684 (6.9%) were in the humerus, 365 (3.7%) in the pelvis, 2041 (20.7%) in the femur and 1660 (16.8%) in the tibia. Most grafts were osteoarticular (2481, 26.7%) and intercalary 2112 (22.7%) allografts. In 461 (5.0%), vascularized fibula grafts (VFGs) were used in combination with recycled autografts. Recycled grafts were reported in 1573 (16.9%) of the cases, and allograft-prosthetic composites in 1673 (18.0%). The pelvis and the tibia had the highest incidence of BGI (20.4% and 11.0%, respectively). The most reported first treatment was debridement and implant retention (DAIR) in 187 (42.8%) cases and two-stage revision with graft removal in 152 (34.8%). Very little data are reported on the final outcome specified by site or type of graft. Conclusions: This systematic review of the literature confirms a high incidence of infections in biologic reconstructions after resections of primary bone tumors. Despite DAIR being a viable attempt, in most cases, a two-stage approach with graft removal and reconstruction with endoprosthesis presented the highest chance to overcome infection, guaranteeing a reconstruction. We emphasize the need for future multicentric studies to focus on the management of infections after biological reconstructions in bone sarcomas.

Parallel Reconstruction of Vascularized Fibula Autograft for Treatment of Complications after Resection of Malignant Tumor from the Thigh

SUMMARY

The authors herein introduce a modification of parallel reconstruction with a vascularized fibula autograft (VFA) for cases of femur allograft complications. Conventional parallel reconstruction, in which the fibula with its vascular pedicle is placed on the medial side of the femur and allogeneic bone, may be an effective means to solve the allograft complications. However, the limited contact area between the fibula and femur/allogeneic bone can affect the bone healing ability. Furthermore, the rigid internal fixation method for the VFA may cause stress shielding and result in bone resorption. The authors propose the use of modified parallel reconstruction of the VFA with fibula expansion and titanium cable fixation for patients with allograft-host junction nonunion, allogeneic bone fracture, and femoral shaft fracture after surgical removal of a malignant tumor from the thigh. The modified parallel reconstruction has been performed on 5 patients (2 patients underwent fibular expansion). All 5 patients with 7 nonunions of the allograft-host junction or fracture were followed up for 33.2 months. The length of fibular graft was 10 to 20 cm, with an average of 15.0 cm. The union rate of allograft-host junction and fracture was 100% (7 of 7), and the union time was 15.9 months. This modified parallel reconstruction technique can achieve satisfactory union in treatment of the above complications.

Factors Influencing Nonunion and Fracture Following Biological Intercalary Reconstruction for Lower-Extremity Bone Tumors: A Systematic Review and Pooled Analysis

OBJECTIVES

To determine nonunion rate, fracture rate, and their risk factors following biological intercalary reconstruction for lower extremity bone tumors.

METHODS

A systematic review and pooled analysis were conducted. PubMed, Embase, and Wiley Cochrane Library were searched from inception up to June 01, 2020. Studies concerning biological intercalary reconstruction after resection of lower extremity bone tumors were included. Overall nonunion and fracture rates were calculated. For studies reporting patient outcomes individually with precise graft characteristics and fixation methods, the individual data were extracted. Patients with demographical and clinical characteristics, including age, sex, tumor location, graft characteristics, and fixation method, were pooled for a multivariate analysis. For each factor of interest, odds ratio (OR), 95% confidence interval (95% CI), and p-value from logistic regression were reported.

RESULTS

A total of 2776 articles were identified from the initial literature search and 76 studies (2052 patients) were included. Sixty-nine studies were case series and seven were comparative studies. The overall nonunion rate was 19% (382/2052; range: 0%-53%), and the overall fracture rate was 17% (344/2052; range: 0%-75%). Thirty of the 76 studies (362 patients) reported patients' characteristics individually and were thus included in the pooled multivariate analysis. Intramedullary nail fixation was associated with a significantly higher nonunion rate compared to plate fixation (OR = 2.2, 95% CI: 1.23-4.10, p = 0.009). Reconstruction with a vascularized fibula graft had a statistically non-significant lower nonunion rate than reconstruction without the graft (OR = 0.6, 95% CI: 0.34-1.07, p = 0.086). Devitalized autografts had a lower fracture risk than allografts (OR = 0.3, 95% CI: 0.14-0.64, p = 0.002), and males tended to have higher fracture risk than females (OR = 2.1, 95% CI: 1.00-4.44, p = 0.049).

CONCLUSIONS

Reconstruction with intramedullary nail fixation is related to an elevated risk of nonunion. Allografts and males have a higher fracture risk than devitalized autografts and females, respectively. Further high-quality comparative analyses with large sample sizes and adequate follow-up duration are needed to validate these findings.

3D Customized Biological Tibial Intramedullary Nail Fixation for the Treatment of Fracture after Massive Allograft Bone Transplantation of Tibial Osteosarcoma: A Case Report

Allograft bone fractures are critical complications in massive allograft bone transplantations. There are limited studies available on the application of 3D printing for massive allograft bone transplantation complications, and no related reports on the treatment of an allograft bone fracture with a complete biological intramedullary nail. A complex case of allograft bone fracture after massive bone transplantation for a right tibial osteosarcoma was treated with fixation of an individualized 3D printed biological tibial intramedullary nail. Prior to the operation, the intramedullary nail was designed and printed based on the results of computed tomography examination of the affected limb, and the surface of the intramedullary nail was treated with a hydroxyapatite coating. Intraoperatively, the intramedullary nail was implanted according to the preoperative 3D design plan. The intraoperative and postoperative examinations showed that the 3D printed intramedullary nail achieved good matching between the implant and the medullary cavity, and the biological coating integrated well with surrounding bone. The follow-up results 44 months postoperatively showed that the patient was satisfied with the surgical results, where his ankle function met his daily needs, and the Musculoskeletal Tumor Society score was 24. 3D printing tibial intramedullary nail fixation can be successful in the treatment of allograft bone fractures and should be considered as a treatment of choice. In this case, the intramedullary nail matched the surrounding bone well, had good osseointegration, and the patient regained basic function.

Automatic Registration and Error Color Maps to Improve Accuracy for Navigated Bone Tumor Surgery Using Intraoperative Cone-Beam CT

Computer-assisted surgery (CAS) can improve surgical precision in orthopaedic oncology. Accurate alignment of the patient’s imaging coordinates with the anatomy, known as registration, is one of the most challenging aspects of CAS and can be associated with substantial error. Using intraoperative, on-the-table, cone-beam computed tomography (CBCT), we performed a pilot clinical study to validate a method for automatic intraoperative registration.

How the Choice of Osteosynthesis Affects the Complication Rate of Intercalary Allograft Reconstruction? A Systematic Review and Meta-analysis

BACKGROUND

There is no clear consensus on the optimal type of fixation in intercalary allograft reconstruction. In this study, we aimed to compare the rate of most common complications following the plate and nail fixation of the intercalary allograft.

MATERIALS AND METHODS

We searched PubMed, EMBASE, Web of Science, Scopus, and Cochrane Library. Studies in which the complication rate of the single bridging plate and intramedullary nail fixation was extractable were included. Studies that used extra procedures such as cementation and fibular vascular graft augmentation were excluded. The primary outcome was the fixation-specific rate of nonunion. Secondary outcomes were the fixation-specific rate of fracture, infection, and local recurrence.

RESULTS

In total, 13 studies with 431 reconstructions (352 reconstructions in the plate group and 79 reconstructions in the intramedullary nailing group) were included in this study. In the plate fixation, the rate of nonunion, fracture, infection and local recurrence was 12%, 11%, 11%, and 3%, respectively. In the intramedullary nail fixation, the rate of nonunion, fracture, infection, and local recurrence was 37%, 5%, 4%, and 0%, respectively. The rate of nonunion was significantly higher in the intramedullary nail group (OR = 6.34; 95% CI 2.98-13.49, P < 0.001). The rate of fracture, infection, and local recurrence was not significantly different between the two fixation methods.

CONCLUSIONS

Intramedullary nail is associated with a significantly higher rate of nonunion. Since the rate of other complications was not significantly different between the two osteosynthesis types, plate fixation could be considered as a better type of fixation.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s43465-021-00563-7.

Cement Intercalary Reconstruction After Bone Tumor Resection

The optimal type of reconstruction after intercalary tumor resection is unclear. Megaprosthetic and biologic reconstructions may restore bone stock, but their complexity may result in complications and delays in rehabilitation and initiation of adjuvant treatment. Instead, cement spacer permanent reconstruction can be performed as index surgery. The authors studied the files of 20 patients who had bone tumors of the humerus and femur and underwent wide margin resection and permanent cement spacer intercalary reconstruction. Mean follow-up was 52 months (range, 2-255 months). The authors evaluated the survival and function of the patients and the outcome of the cement spacer reconstructions. Five patients who had metastatic bone disease died of their disease with their cement spacer reconstruction in place without complications. One patient who had bone sarcoma experienced a local recurrence that was treated with hip disarticulation. Three patients who had bone sarcomas were converted to biologic reconstruction because of disease remission and had improved prognosis without complications related to cement spacer reconstruction. Two patients experienced mechanical failure of femoral reconstruction and underwent revision with an intercalary biologic reconstruction. No patient who had a cement spacer humeral reconstruction experienced a complication, and no patient experienced infection of the reconstruction. Mean Musculoskeletal Tumor Society score of the patients with cement spacer humeral and femoral reconstructions was 85% and 82%, respectively. [Orthopedics. 2021;44(4):e593-e599.].

Is the Capanna Technique a Reliable Method for Revision Surgery after Failure of Previous Limb-Salvage Surgery?

BACKGROUND

Reconstruction of a massive bone defect caused by previous failed limb-salvage surgery in patients with bone sarcoma is challenging. Many procedures have been used, but they all have their inherent disadvantages. The Capanna technique has demonstrated good functional outcomes and a low incidence of complications in primary reconstructive surgery of massive bone defect. However, few studies have focused on its usage in revision surgery after failed primary limb-salvage surgery.

METHODS

Between June 2011 and January 2017, 13 patients underwent revision surgery with the Capanna technique for reconstruction of a secondary segmental bone defect caused by a previous failed surgical procedure. The demographics, operating procedures, graft union, functional outcomes, oncologic outcomes, and postoperative complications of each patient were recorded.

RESULTS

The current study investigated 13 patients. The rate of limb salvage was 100 %. Bone union was achieved for all patients during a mean time of 8.54 ± 2.15 months (range 4-11 months) at the fibula-host bone junction and 14.92 ± 2.33 months (range 12-21 months) at the allograft-host bone junction. The postoperative complications included wound healing issues and internal fixation loosening. Allograft fracture, nonunion, and infection were not observed. All the patients achieved good functional outcomes, with a Musculoskeletal Tumor Society (MSTS) score of 0.86 ± 0.03 at the latest follow-up visit.

CONCLUSIONS

The Capanna technique is a reliable alternative method for revision reconstruction of a segmental bone defect caused by a previous failed surgical procedure.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Does the Addition of a Vascularized Fibula Improve the Results of a Massive Bone Allograft Alone for Intercalary Femur Reconstruction of Malignant Bone Tumors in Children?

BACKGROUND

Massive bone allograft with or without a vascularized fibula is a potentially useful approach for femoral intercalary reconstruction after resection of bone sarcomas in children. However, inadequate data exist regarding whether it is preferable to use a massive bone allograft alone or a massive bone allograft combined with a vascularized free fibula for intercalary reconstructions of the femur after intercalary femur resections in children. Because the addition of a vascularized fibula adds to the time and complexity of the procedure, understanding more about whether it reduces complications and improves the function of patients who undergo these resections and reconstructions would be valuable for patients and treating physicians.

QUESTIONS/PURPOSES

In an analysis of children with bone sarcomas of the femur who underwent an intercalary resection and reconstruction with massive bone allograft with or without a vascularized free fibula, we asked: (1) What was the difference in the surgical time of these two different surgical techniques? (2) What are the complications and number of reoperations associated with each procedure? (3) What were the Musculoskeletal Tumor Society scores after these reconstructions? (4) What was the survival rate of these two different reconstructions?

METHODS

Between 1994 and 2016, we treated 285 patients younger than 16 years with a diagnosis of osteosarcoma or Ewing sarcoma of the femur. In all, 179 underwent resection and reconstruction of the distal femur and 36 patients underwent resection and reconstruction of the proximal femur. Additionally, in 70 patients with diaphyseal tumors, we performed total femur reconstruction in four patients, amputation in five, and a rotationplasty in one. The remaining 60 patients with diaphyseal tumors underwent intercalary resection and reconstruction with massive bone allograft with or without vascularized free fibula. The decision to use a massive bone allograft with or without a vascularized free fibula was probably influenced by tumor size, with the indication to use the vascularized free fibula in longer reconstructions. Twenty-seven patients underwent a femur reconstruction with massive bone allograft and vascularized free fibula, and 33 patients received massive bone allograft alone. In the group with massive bone allograft and vascularized fibula, two patients were excluded because they did not have the minimum data for the analysis. In the group with massive bone allograft alone, 12 patients were excluded: one patient was lost to follow-up before 2 years, five patients died before 2 years of follow-up, and six patients did not have the minimum data for the analysis. We analyzed the remaining 46 children with sarcoma of the femur treated with intercalary resection and biological reconstruction. Twenty-five patients underwent femur reconstruction with a massive bone allograft and vascularized free fibula, and 21 patients had reconstruction with a massive bone allograft alone. In the group of children treated with massive bone allograft and vascularized free fibula, there were 17 boys and eight girls, with a mean ± SD age of 11 ± 3 years. The diagnosis was osteosarcoma in 14 patients and Ewing sarcoma in 11. The mean length of resection was 18 ± 5 cm. The mean follow-up was 117 ± 61 months. In the group of children treated with massive bone allograft alone, there were 13 boys and eight girls, with a mean ± SD age of 12 ± 2 years. The diagnosis was osteosarcoma in 17 patients and Ewing sarcoma in four. The mean length of resection was 15 ± 4 cm. The mean follow-up was 130 ± 56 months. Some patients finished clinical and radiological checks as the follow-up exceeded 10 years. In the group with massive bone allograft and vascularized free fibula, four patients had a follow-up of 10, 12, 13, and 18 years, respectively, while in the group with massive bone allograft alone, five patients had a follow-up of 10 years, one patient had a follow-up of 11 years, and another had 13 years of follow-up. In general, there were no important differences between the groups in terms of age (mean difference 0.88 [95% CI -0.6 to 2.3]; p = 0.26), gender (p = 0.66), diagnosis (p = 0.11), and follow up (mean difference 12.9 [95% CI-22.7 to 48.62]; p = 0.46). There was a difference between groups regarding the length of the resection, which was greater in patients treated with a massive bone allograft and vascularized free fibula (18 ± 5 cm) than in those treated with a massive bone allograft alone (15 ± 4 cm) (mean difference -3.09 [95% CI -5.7 to -0.4]; p = 0.02). Complications related to the procedure like infection, neurovascular compromise, and graft-related complication, such as fracture and nonunion of massive bone allograft or vascularized free fibula and implant breakage, were analyzed by chart review of these patients by an orthopaedic surgeon with experience in musculoskeletal oncology. Survival of the reconstructions that had no graft or implant replacement was the endpoint. The Kaplan-Meier test was performed for a survival analysis of the reconstruction. A p value less than 0.05 was considered significant.

RESULTS

The surgery was longer in patients treated with a massive bone allograft and vascularized free fibula than in patients treated with a massive bone allograft alone (10 ± 0.09 and 4 ± 0.77 hours, respectively; mean difference -6.8 [95% CI -7.1 to -6.4]; p = 0.001). Twelve of 25 patients treated with massive bone allograft and vascularized free fibula had one or more complication: allograft fracture (seven), nonunion (four), and infection (four). Twelve of 21 patients treated with massive bone allograft alone had the following complications: allograft fracture (five), nonunion (six), and infection (one). The mean functional results were 26 ± 4 in patients with a massive bone allograft and vascularized free fibula and 27 ± 2 in patients with a massive bone allograft alone (mean difference 0.75 [95% CI -10.6 to 2.57]; p = 0.39). With the numbers we had, we could not detect a difference in survival of the reconstruction between patients with a massive bone allograft and free vascularized fibula and those with a massive bone allograft alone (84% [95% CI 75% to 93%] and 87% [95% CI 80% to 94%], respectively; p = 0.89).

CONCLUSION

We found no difference in the survival of reconstructions between patients treated with a massive bone allograft and vascularized free fibula and patients who underwent reconstruction with a massive bone allograft alone. Based on this experience, our belief is that we should reconstruct these femoral intercalary defects with an allograft alone and use a vascularized fibula to salvage the allograft only if a fracture or nonunion occurs. This approach would have resulted in about half of the patients we treated not undergoing the more invasive, difficult, and risky vascularized procedure.Level of Evidence Level III, therapeutic study.

Improved osteogenesis in rat femur segmental defects treated with human allograft and zinc adjuvants

Bone allograft is widely used to treat large bone defects or complex fractures. However, processing methods can significantly compromise allograft osteogenic activity. Adjuvants that can restore the osteogenic activity of processed allograft should improve clinical outcomes. In this study, zinc was tested as an adjuvant to increase the osteogenic activity of human allograft in a Rag2 null rat femoral defect model. Femoral defects were treated with human demineralized bone matrix (DBM) mixed with carboxy methyl cellulose containing ZnCl₂ (0, 75, 150, 300 µg) or Zn stearate (347 µg). Rat femur defects treated with DBM-ZnCl₂ (75 µg) and DBM-Zn stearate (347 µg) showed increased calcified tissue in the defect site compared to DBM alone. Radiograph scoring and µCT (microcomputed tomography) analysis showed an increased amount of bone formation at the defects treated with DBM-Zn stearate. Use of zinc as an adjuvant was also tested using human cancellous bone chips. The bone chips were soaked in ZnCl₂ solutions before being added to defect sites. Zn adsorbed onto the chips in a time- and concentration-dependent manner. Rat femur defects treated with Zn-bound bone chips had more new bone in the defects based on µCT and histomorphometric analyses. The results indicate that zinc supplementation of human bone allograft improves allograft osteogenic activity in the rat femur defect model.

Intercalary reconstruction following resection of diaphyseal bone tumors: A systematic review

INTRODUCTION

The options for the reconstruction of diaphyseal defects following the resection of bone tumors include biological or prosthetic implants. The purpose of our study was to evaluate different types of intercalary reconstruction techniques, including massive bone allograft, extracorporeal devitalized autograft, vascularized free fibula, and modular prosthesis.

METHODS

We performed a systematic review of articles using the terms diaphyseal bone tumor and intercalary reconstruction. All the studies reporting the non-oncological complications such as infection, nonunion and fracture of the intercalary reconstructions were included. We excluded articles published before 2000 or did not involve humans in the study. Case reports, reviews, technique notes and opinion articles were also excluded based on the abstracts. Thirty-three articles included in this review were then studied to evaluate failure rates, complications and functional outcome of different surgical intercalary reconstruction techniques.

RESULTS

Nonunion rates of allograft ranged 6%-43%, while aseptic loosening rates of modular prosthesis ranged 0%-33%. Nonunion rates of allograft alone and allograft with a vascularized fibula graft ranged 6%-43% and 0%-33%, respectively. Fracture rates of allograft alone and allograft with a vascularized fibula graft ranged 7%-45% and 0%-44%, respectively. Infection rates of allograft alone and allograft with a vascularized fibula graft ranged 0%-28% and 0%-17%, respectively. All of the allograft (range: 67%-92%), extracorporeal devitalized autograft including irradiation (87%), autoclaving (70%), pasteurization (88%), low-heat (90%) or freezing with liquid nitrogen (90%), and modular prosthesis (range: 77%-93%) had similar Musculoskeletal Tumor Society functional scores. Addition of a vascularized fibula graft to allograft did not affect functional outcome [allograft with a vascularized fibula graft (range: 86%-94%) vs. allograft alone (range: 67%-92%)].

CONCLUSION

Aseptic loosening rates of modular prosthesis seem to be less than nonunion rates of allograft. Adding a vascularized fibula graft to allograft seems to increase bone union rate and reduce the risk of fractures and infections, though a vascularized fibula graft needs longer surgical time and has the disadvantage of donor site morbidity. These various intercalary reconstruction techniques with or without a vascularized fibula autograft had similar functional outcome.

Intercalary Reconstruction of the "Ultra-Critical Sized Bone Defect" by 3D-Printed Porous Prosthesis After Resection of Tibial Malignant Tumor

Purpose

This study aimed to evaluate the early stability, limb function, and mechanical complications of 3D-printed porous prosthetic reconstruction for "ultra-critical sized bone defects" following intercalary tibial tumor resections.

Methods

This study defined an "ultra-critical sized bone defect" in the tibia when the length of segmental defect in the tibia was >15.0 cm or >60% of the full tibia and the length of the residual fragment in proximal or distal tibia was between 0.5 cm and 4.0 cm. Thus, five patients with "ultra-critical sized bone defects" following an intercalary tibial malignant tumor resection treated with 3D-printed porous prosthesis between June 2014 and June 2018 were retrospectively reviewed. Patient information, implants design and fabrication, surgical procedures, and early clinical outcome data were collected and evaluated.

Results

Among the five patients, three were male and two were female, with an average age of 30.2 years. Pathological diagnoses were two osteosarcomas, one Ewing sarcoma, one pseudo-myogenic hemangioendothelioma, and one undifferentiated pleomorphic sarcoma . The average length of the bone defects following tumor resection was 22.8cm, and the average length of ultra-short residual bone was 2.65cm (range=0.6cm-3.8cm). The mean follow-up time was 27.6 months (range=14.0-62.0 months). Early biological fixation was achieved in all five patients. The average time of clinical osseointegration at the bone-porous interface was 3.2 months. All patients were reported to be pain free and have no limitations in their walking distance. No prosthetic mechanical complications were observed.

Conclusion

Reconstruction of the "ultra-critical sized bone defect" after an intercalary tibial tumor resection using 3D-printed porous prosthesis achieved satisfactory overall early biological fixation and limb function. Excellent primary stability and the following rigid biological fixation were key factors for success. The outcomes of this study were supposed to support further clinical application and evaluation of 3D-printed porous prosthetic reconstruction for "ultra-critical sized bone defects" in the tibia.

Reconstruction with biological methods following intercalary excision of femoral diaphyseal tumors

AIM

The aim of this study was to assess outcomes of biological (nonvascularized fibula grafts and extracorporeal irradiated autologous bone grafts) methods used for reconstruction of intercalary defects after resection of femoral diaphyseal tumors.

MATERIALS AND METHODS

This study included 28 patients who had undergone intercalary resection in femoral diaphyseal tumors between 2011 and 2016. The mean follow-up period was 24 months (range 12-57 months).

RESULTS

The mean union time for diaphyseo-diaphyseal union was 10.5 and 11 months in nonvascularized fibula group and extracorporeal radiotherapy (ECRT) group, respectively. The mean union time for metaphyseo-diaphyseal union was 6.5 months in both nonvascularized fibula and ECRT groups. Six patients had distant metastasis, and one patient had local recurrence. The mean Musculoskeletal Tumor Society score was 28 at the last follow-up. Two patients had surgical site infection in the nonvascularized fibula group. Implant failure was found in one patient of the ECRT group requiring revision surgery. Three patients had nonunion (two from the nonvascularized fibula group and one from the ECRT group).

CONCLUSION

The present study indicates that the biological reconstruction modalities provide good functional outcomes in diaphyseal tumors of femur. Nonvasularized fibula and ECRT-treated autografts reconstruction provides good results, and union timing is comparable. The outcomes of the current study are promising as compared to the results in the reviewed literature. The reconstruction method depends on the resources available at the oncological center and the conversance with the method of the treating surgeon.

Factors Influencing Osseous Union Following Surgical Treatment of Bone Tumors with Use of the Capanna Technique

BACKGROUND

The Capanna technique involves the use of a vascularized fibular graft inlaid in a massive bone graft in intercalary reconstruction for diaphyseal long-bone defects caused by tumor resection. Allograft-host union time varies in different reports, and few studies have focused on the underlying factors affecting union time. The purpose of the present study was to analyze factors relevant to union time and to report complications of the Capanna technique.

METHODS

We identified 60 patients who underwent segmental reconstruction with use of the Capanna technique following tumor resection (in the humerus in 10 patients, the femur in 33 patients, and the tibia in 17 patients). Multivariable linear multiple regression model analysis was performed with allograft-host osseous union time as the dependent variable. Union time was evaluated on radiographs. Independent variables included age, tumor site, adjuvant treatment, a previous surgical procedure, defect length, fixation method, and fibular viability. A retrieved specimen of the composite was histologically assessed.

RESULTS

The mean defect length was 16 cm. All allografts and host bone united, with the mean time to union of 13 months (range, 6 to 27 months). Prolonged union time was associated with devitalization of the fibular graft (p < 0.001), use of chemotherapy (p = 0.031), and a previous surgical procedure (p = 0.048). Patient age (p = 0.742), amount of resection (p = 0.907), operative site (p = 0.508), and fixation method (p = 0.105) were not associated with union time. On histological analysis, we found that the allograft-host cortical junction was united by callus from both periosteum of the host bone and the fibula.

CONCLUSIONS

The Capanna technique appears to be a reliable method for intercalary reconstruction with a low rate of complications. Devitalization of the transplanted fibula, chemotherapy, and a previous surgical procedure are adverse factors leading to prolonged union time.

LEVEL OF EVIDENCE

Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Efficacy of a Modified Scoring System to Facilitate Surgical Decision-making for Diaphyseal Malignancies: When is Devitalized Tumor-bearing Autograft of Value?

Objectives

To evaluate the validity of a modified scoring system (MSS) for inferring the bony quality of tumor‐bearing diaphyses and predicting the risk of reconstructive failure after devitalized bone replantation (DBR).

Methods

In this retrospective cohort study, we reviewed the records of 30 patients surgically treated for diaphyseal malignancies between 1996 and 2015. There were 18 male and 12 female subjects; the average age was 34.0 ± 24.5 years (8–82 years). Tumor locations comprised the femur (21), the humerus (4), the tibia (3), the radius (1), and the fibula (1). Histological diagnoses included osteosarcoma (13), metastases (4), Ewing sarcoma (3), chondrosarcoma (3), malignant fibrohistiocytoma (2), periosteal osteosarcoma (1), Langerhans cell sarcoma (1), lymphoma (1), rhabdomyosarcoma (1), and malignant giant cell tumor (1). All primary tumors were rated as stage IIB. Twenty patients underwent DBR. Prosthetic procedures and segmental autografting/allografting were performed in 7 and 3 cases, respectively. MSS (comprising 5 elements: pain, tumor location, bone destruction, localized dimension, and longitudinal dimension) for each patient was calculated in accordance with their preoperative presentations. Outcome measurements included oncological results, outcomes of reconstructions, complications, and functional preservation, presented using the musculoskeletal tumor society (MSTS) scale.

Results

Follow up was available in 29 cases for an average duration of 61.0 ± 49.9 months (12–152 months). Infection occurred in 2 patients (6.9%), primary nonunion in 6 (27.3%), metastases in 9 (31.9%), recurrences in 4 (13.8%), and deaths in 7 (24.1%); 1 subject underwent amputation due to recurrence following endoprosthetic replacement (3.4%). In the DBR group, fractures occurred in 4 cases (21.1%) and nonunion in 5 (25%); internal fixation was related to nonunion (nails, 44.4% vs plates, 9.1%, P = 0.02). MSS was associated with fractures of devitalized autografts (11.0 ± 1.2 vs 8.3 ± 1.8, P = 0.01); the system was efficacious in predicting chances of fractures of these grafts (P = 0.02). MSS ≥ 10 (with false positive rate ≤ 6.7%) suggested increased fracture probability (≥22.7%) after DBR; therefore, 10 was considered a cutoff value.

Conclusions

Diaphyseal malignancies with MSS ≥10 may contraindicate DBR for increased chances of reconstructive failure. In this situation, alternative procedures are advisable. Further investigations are warranted to assess the efficacy of MSS in implying the validity of DBR for diaphyseal malignancies.

Microsurgery in musculoskeletal oncology

Sarcomas are rare mesenchymal bone and soft tissue tumors of the musculoskeletal system. In the past, the primary treatment modality was amputation of the involved limb and the 5-year survival was very low for high-grade tumors. During the last three decades, limb salvage has become the rule rather than the exception and the use of neoadjuvant and adjuvant therapies (radiation and chemotherapy) has dramatically increased disease-free survival. Reconstruction of large bone and soft tissue defects, though, still remains a significant challenge in sarcoma patients. In particular, vascularized tissue transfer has proved extremely helpful in dealing with complex bone and soft tissue or functional defects that are frequently encountered as a result of the tumor or as a complication of surgery and adjuvant therapies. The principles, indications and results of microsurgical reconstruction differ from trauma patients and are directly related not only to the underlying disease process, but also to the local and systemic therapeutic modalities applied to the individual patient. Although plastic reconstruction in the oncological patients is not free of complications, usually these complications are manageable and do not jeopardize oncological outcome. The overall treatment strategy should be tailored to the patient's and sarcoma profile.

Short-term outcomes of reconstruction subsequent to intercalary resection of femoral diaphyseal metastatic tumor with pathological fracture: Comparison between segmental allograft and intercalary prosthesis

Reconstruction of bone defects following femoral diaphyseal tumor resection is challenging. Segmental allograft (SA) and intercalary prosthesis (IP) are the most common reconstruction methods for femoral diaphyseal metastatic tumors with pathological fracture. However, whether the complications and functional outcomes differ between SA and IP remains unclear. To compare the clinical outcomes and complications for patients treated with SA reconstruction or IP replacement for femoral shaft tumors, 34 patients who had undergone intercalary resection for metastatic tumor with pathological fracture in the femoral diaphysis were evaluated. Of these, 18 had received SA and 16 IP. There were 11 males, and 24 females, with a mean age of 64.5±11.3 years. The most common sites of primary metastases were lung (26.5%), breast (17.6%) and liver (14.7%). The visual analog scale (VAS), implant-related complications and the Musculoskeletal Tumor Society (MSTS) scores for each patient were collected. The follow-up period for patients ranged from 2 to 27 months. At the most recent follow-up, 28 patients had succumbed to mortality, with a mean survival time of 6.9±3.7 months for the IP group and 7.4±3.0 months for the SA group. Patients with IP had a significantly shorter time to full weight bearing and hospitalization time than those who received SA (P=0.003 and P=0.002, respectively). The rates of overall complications and implant-related complications were significantly lower for IP as compared with SA (18.8 vs. 66.7%, P=0.007; 12.5 vs. 55.6%, P=0.013). The reoperation rate of the SA group was higher than that of the IP group (38.9 vs. 12.5%), however the difference between the two groups was statistically insignificant (P=0.125). MSTS scores were significantly higher for the IP group as compared with the SA group at one month after surgery (IP, 26.7±1.6 vs. SA, 20.3±1.5; P<0.05), without a significant difference at the final follow-up. There were no statistically significant differences in age, sex, length of resection, follow-up time, operative time or blood loss between the two groups. In summary, IP reconstruction may provide improved early functional outcomes and fewer early complications, particularly for patients with a shorter life expectancy due to femoral metastatic tumors with pathological fracture.

[Effectiveness of unicompartment allografts replacement for bone tumor around the knee]

Objective

To analyze the effectiveness of unicompartment allografts replacement for reconstructing bone defect after bone tumor resection around knee.

Methods

Between January 2007 and January 2014, a total of 9 patients received unicompartment allografts replacement to treat bone tumor around the knee, including 6 males and 3 females, with an average age of 25.8 years (range, 17-38 years). There were 7 patients with bone giant cell tumor (postoperative recurrence of bone giant cell tumor in 1 case) and 2 patients with chondromyxoid fibroma. The tumors were located at the distal femur in 7 cases and proximal tibia in 2 cases, and the tumors were almost at the lateral limbs. The symptom duration was 2-5 months (mean, 3.2 months). The size of lesion ranged from 6 cm×2 cm to 9 cm×4 cm by X-ray film and MRI; and the metastasis was excluded by CT. The length of the allograft was 8.0-9.2 cm (mean, 8.6 cm).

Results

The intraoperative blood loss volume was 400-550 mL (mean, 480 mL); and 0-3 U of erythrocyte was transfused after operation. The continuous exudate of incision occurred in 1 patient, and cured after 3 months; the other incisions healed primarily at 2 weeks after operation. All patients were followed up 3-10 years (mean, 6 years). No operation area infection, allograft bone poor healing or rupture was found. At 1 year after operation, the knee range of motion was 90-110° (mean, 100°); the Musculoskeletal Tumor Society score was 24-29 (mean, 26). Low density area (osteolysis) was found in 6 allografts; no articular surface collapse, hairline fracture, or fracture was found in patients; callus formation was observed in the contact surface between the allograft and the host bone, and the cortical bone showed good continuity.

Conclusion

Unicompartment allografts replacement can provide good support and function in terms of bone tumor resection, and achieve good effectiveness by biological reconstruction.

Intercalary reconstructions after bone tumor resections: a review of treatments

An intercalary reconstruction is defined as replacement of the diaphyseal portion of a long bone after segmental skeletal resection (diaphysectomy). Intercalary reconstructions typically result in superior function compared to other limb-sparing procedures as the patient's native joints above and below the reconstruction are left undisturbed. The most popular reconstructive options after segmental resection of a bone sarcoma include allografts, vascularized fibula graft, combined allograft and vascularized fibula, segmental endoprostheses, extracorporeal devitalized autograft, and segmental transport using the principles of distraction osteogenesis. This article aims to review the indications, techniques, limitations, pros and cons, and complications of the aforementioned methods of intercalary bone tumor resections and reconstructions in the context of the ever-growing, brave new field of limb-salvage surgery.

Is there still a role for osteoarticular allograft reconstruction in musculoskeletal tumour surgery? a long-term follow-up study of 38 patients and systematic review of the literature

AIMS

To assess complications and failure mechanisms of osteoarticular allograft reconstructions for primary bone tumours.

PATIENTS AND METHODS

We retrospectively evaluated 38 patients (28 men, 74%) who were treated at our institution with osteoarticular allograft reconstruction between 1989 and 2010. Median age was 19 years (interquartile range 14 to 32). Median follow-up was 19.5 years (95% confidence interval (CI) 13.0 to 26.1) when 26 patients (68%) were alive. In addition, we systematically searched the literature for clinical studies on osteoarticular allografts, finding 31 studies suitable for analysis. Results of papers that reported on one site exclusively were pooled for comparison.

RESULTS

A total of 20 patients (53%) experienced graft failure, including 15 due to mechanical complications (39%) and three (9%) due to infection. In the systematic review, 514 reconstructions were analysed (distal femur, n = 184, 36%; proximal tibia, n = 136, 26%; distal radius, n = 99, 19%; proximal humerus, n = 95, 18%). Overall rates of failure, fracture and infection were 27%, 20%, and 10% respectively. With the distal femur as the reference, fractures were more common in the humerus (odds ratio (OR) 4.1, 95% CI 2.2 to 7.7) and tibia (OR 2.2, 95% CI 1.3 to 4.4); infections occurred more often in the tibia (OR 2.2, 95% CI 1.3 to 4.4) and less often in the radius (OR 0.1, 95% CI 0.0 to 0.8).

CONCLUSION

Osteoarticular allograft reconstructions are associated with high rates of mechanical complications. Although comparative studies with alternative techniques are scarce, the risk of mechanical failure in our opinion does not justify routine employment of osteoarticular allografts for reconstruction of large joints after tumour resection. Cite this article: Bone Joint J 2017;99-B:522-30.

Radial Shaft Reconstruction With an Intercalary Endoprosthesis Following Resection of Metastatic Tumor

Improvements in imaging and treatment of musculoskeletal tumors have increased the variety of options for reconstruction following joint-sparing diaphyseal resection. The purpose of this case series was to show that reconstruction of malignant tumors of the radial shaft with an intercalary prosthesis may be an option for patients with segmental bone loss. Three consecutive patients underwent wide resection of the radial diaphysis followed by reconstruction with a custom intercalary prosthesis. A custom intercalary prosthesis with lap joint design was used in all 3 cases. Mean follow-up was 18 months (range, 9-25 months). All patients were weight bearing as tolerated 1 week postoperatively. At the most recent follow-up, patients' mean elbow flexion and extension arc was 137° (range, 130°-140°). At the forearm, mean supination was 60° (range, 30°-90°) and mean pronation was 70° (range, 60°-90°). At the wrist, mean palmar flexion was 80° (range, 70°-90°) and mean dorsiflexion was 80° (range, 70°-90°). All patients reported minimal to no pain and no significant functional limitations. Mean Musculoskeletal Tumor Society score was 26/30 (87%). Reconstruction with an intercalary prosthesis is a viable option for patients with metastatic disease of the radial shaft. All patients had satisfactory results and early return to function; none required return to the operating room. Possible advantages of reconstruction with an intercalary prosthesis compared with reconstruction with a bone graft or polymethylmethacrylate osteosynthesis include early return to function and minimal weight-bearing restrictions postoperatively. [Orthopedics. 2017; 40(2):e242-e247.].

Simultaneous reconstruction of the bone and vessels for complex femoral defect

Background

Several methods have been reported for intercalary reconstruction of femoral defects. Of these, free vascularized fibula grafts (FVFG) are preferred because of their durability, bone-healing potential, and tolerance to infection. If the bone tumor invades the femoral vessels, simultaneous vascular reconstruction also becomes necessary and significant technical hurdles make limb salvage difficult.

Case presentation

We present a 10-year-old girl who underwent limb-sparing surgery for a distal femur osteosarcoma. The femoral defect was 15 cm long, and the femoral vessel defect was 10 cm long. The femur was reconstructed with bilateral FVFG, and the femoral vessels were reconstructed with saphenous vein grafts. The grafts survived without vascular compromise, and the affected limb was preserved successfully.

Conclusions

Combined use of bilateral FVFG and autologous vein grafts makes limb-sparing surgery for a large osteosarcoma of the femur possible.

What Is the Outcome of Allograft and Intramedullary Free Fibula (Capanna Technique) in Pediatric and Adolescent Patients With Bone Tumors?

BACKGROUND

After bone tumor resection, reconstruction for limb salvage surgery can be challenging because of the resultant large segmental bony defects. Structural allografts have been used to fill these voids; however, this technique is associated with high complication rates. To circumvent the complications associated with this procedure, massive bony allografts have been supplemented with an intramedullary vascularized free fibula. However, few studies have examined the outcomes using this technique in the pediatric and adolescent populations.

QUESTIONS/PURPOSES

The purpose of this study was to examine the revision-free survival using he Capanna technique for limb salvage for pediatric lower limb salvage. We attempted to answer the following questions: (1) What was the overall limb salvage rate along with incidence of reoperation and complications? (2) How did pediatric and adolescent patients functionally perform after this technique? (3) What was the incidence of late complications including infection and fracture? (4) What was the incidence of limb length discrepancy?

METHODS

Eighteen pediatric patients who underwent lower extremity limb salvage with the use of cadaveric allograft and intramedullary free fibular transfer (Capanna technique) were identified. There were nine boys males and nine girls with a mean age of 11 years (range, 5-18 years) and mean followup of 8 years (range, 2-15 years), respectively. All patients had at least 2 years followup. Three patients have not been seen in followup during the past 5-years; however, all had made it to their 5-year clinical followup. The patients' medical records were reviewed for clinical and functional outcomes as well as postoperative complications. Time to union was recorded through an evaluation of radiographs. Mankin functional outcome and Musculoskeletal Tumor Society (MSTS) rating scale were recorded for each patient.

RESULTS

The overall limb salvage rate was 94%. Fourteen patients underwent an additional surgical procedure. Six patients underwent additional procedure(s) to treat a symptomatic nonunion. Seventeen of the patients had a good or excellent Mankin score with a mean MSTS rating of 93% at last followup. Six of the patients underwent a limb length modification procedure.

CONCLUSIONS

Use of large allografts in conjunction with intramedullary vascularized free fibulas appears to be a reliable method for the reconstruction of large bony tumors of the lower extremity in this population, although we did not directly compare this with allografts alone in our study. The use of locked plates may improve union times. The proportion of patients achieving limb preservation was high and complication rates are acceptable.

LEVEL OF EVIDENCE

Level IV, therapeutic study.

Outcomes of a Modular Intercalary Endoprosthesis as Treatment for Segmental Defects of the Femur, Tibia, and Humerus

BACKGROUND

Resection of diaphyseal bone tumors for local tumor control and stabilization often results in an intercalary skeletal defect and presents a reconstructive challenge for orthopaedic surgeons. Although many options for reconstruction have been described, relatively few studies report on the functional outcomes and complications of patients treated with modular intercalary endoprostheses.

QUESTIONS/PURPOSES

The objectives of this study were to examine clinical outcomes after reconstruction with a modular intercalary endoprosthesis with a specific focus on (1) the rate of complication or failure; (2) differences in complication rates by anatomic site; (3) functional results as assessed by the Musculoskeletal Tumor Society System (MSTS); and (4) differences in complication rate between patients treated with cemented versus noncemented fixation.

METHODS

We conducted a retrospective chart review of patients treated with a modular intercalary endoprosthesis from three musculoskeletal oncology centers from 2008 to 2013. The indication for use of this intercalary endoprosthesis was segmental bone loss from aggressive or malignant tumor with sparing of the joint above and below and deemed unsuitable for biologic reconstruction. No other implant was used for this indication during this period. During this period, 41 patients received a total of 44 intercalary implants, which included 18 (40%) humeri, 5 (11%) tibiae, and 21 (48%) femora. There were 27 (66%) men and 14 (34%) women with a mean age of 63 years (range, 18–91 years). Eight patients (20%) had primary bone tumors and 33 (80%) had metastatic lesions. Thirty-five (85%) patients were being operated on as an initial treatment and six (15%) for revision of a previous reconstruction. Twenty-nine (66%) procedures had cemented stem fixation and 15 (34%) were treated with noncemented fixation. The overall mean followup was 14 months (range, 1–51 months). Patients with primary tumors had a mean followup of 19 months (range, 4–48 months) and patients with metastatic disease had a mean followup of 11 months (range, 1–51 months). Causes of implant failure were categorized according to Henderson et al. [19] into five types as follows: Type I (soft tissue failure), Type II (aseptic loosening), Type III (structural failure), Type IV (infection), and Type V (tumor progression). At 2 years of followup, 38 (93%) of these patients were accounted for with three (7%) lost to followup. MSTS functional assessment was available for 39 of 41 patients (95%).

RESULTS

At latest followup of these 41 patients, 14 (34%) patients were dead of disease, two patients (5%) dead of other causes, seven (17%) are continuously disease-free, one (2%) shows no evidence of disease, and 17 (41%) are alive with disease. There were 12 (27%) nononcologic complications. Five (11%) of these were Type II failures occurring in noncemented implants between the stem and bone, and six (14%) were Type III failures occurring in cemented implants at the clamp-rod implant interface. One patient developed a deep infection (2%, Type IV failure) and underwent removal of the implant. Additionally, one patient (2%, Type V failure) was treated by amputation after local progression of his metastatic disease. Complications were more common in femoral reconstructions than in tibial or humeral reconstructions. Twelve of 21 patients (57%) with femoral reconstructions had complications versus 0% of tibial or humeral reconstructions (0 of 23; odds ratio [OR], 62; 95% confidence interval [CI], 3–1154; p < 0.0001). The mean overall MSTS score was 77%. Implants with cemented fixation (29) had higher mean MSTS scores when compared with implants with noncemented (15) fixation (84% versus 66%, p = 0.0017). The complication rate was 33% in noncemented cases and 21% in cemented cases (p = 0.39); however, Type II failure at the bone-stem interface was associated with noncemented fixation and Type III failure at the clamp-rod interface was associated with cemented fixation (OR, 143; 95% CI, 2.413–8476; p = 0.0022).

CONCLUSIONS

The results of this study indicate that this modular intercalary endoprosthesis yields equivalent results to other studies of intercalary endoprostheses in terms of MSTS scores. We found that patients treated with intercalary endoprostheses in the femur experienced more frequent complications than those treated for lesions in either the humerus or tibia and that the femoral complication rate of this endoprosthesis is higher when compared with other studies of intercalary endoprostheses for femoral reconstruction. Further studies are still needed to determine the long-term outcomes of this endoprosthesis in patients with primary tumors where longevity of the implant is of more importance than in the metastatic setting. We recommend cemented fixation for this intercalary modular endoprostheses because this provides improved MSTS scores and allows immediate return to weightbearing, which is of advantage to metastatic patients with limited lifespans. Level of Evidence: Level III, therapeutic study.

Intercalary reconstruction after wide resection of malignant bone tumors of the lower extremity using a composite graft with a devitalized autograft and a vascularized fibula

Introduction. Although several intercalary reconstructions after resection of a lower extremity malignant bone tumor are reported, there are no optimal methods which can provide a long-term reconstruction with fewest complications. We present the outcome of reconstruction using a devitalized autograft and a vascularized fibula graft composite. Materials and Methods. We conducted a retrospective review of 11 patients (7 males, 4 females; median age 27 years) undergoing reconstruction using a devitalized autograft (pasteurization (n = 6), deep freezing (n = 5)) and a vascularized fibula graft composite for lower extremity malignant bone tumors (femur (n = 10), tibia (n = 1)). Results. The mean period required for callus formation and bone union was 4.4 months and 9.9 months, respectively. Four postoperative complications occurred in 3 patients: 2 infections (1 pasteurized autograft, 1 frozen autograft) and 1 fracture and 1 implant failure (both in pasteurized autografts). Graft removal was required in 2 patients with infections. The mean MSTS score was 81% at last follow-up. Conclusions. Although some complications were noted in early cases involving a pasteurized autograft, our novel method involving a combination of a frozen autograft with a vascularized fibula graft and rigid fixation with a locking plate may offer better outcomes than previously reported allografts or devitalized autografts.

Intercalary allograft reconstructions following resection of primary bone tumors: a nationwide multicenter study

BACKGROUND

Favorable reports on the use of massive allografts to reconstruct intercalary defects underline their place in limb-salvage surgery. However, little is known about optimal indications as reports on failure and complication rates in larger populations remain scarce. We evaluated the incidence of and risk factors for failure and complications, time to full weight-bearing, and optimal fixation methods for intercalary allografts after tumor resection.

METHODS

A retrospective study was performed in all four centers of orthopaedic oncology in the Netherlands. All consecutive patients reconstructed with intercalary (whole-circumference) allografts after tumor resection in the long bones during 1989 to 2009 were evaluated. The minimum follow-up was twenty-four months. Eighty-seven patients with a median age of seventeen years (range, 1.5 to 77.5 years) matched inclusion criteria. The most common diagnoses were osteosarcoma, Ewing sarcoma, adamantinoma, and chondrosarcoma. The median follow-up period was eighty-four months (range, twenty-five to 262 months). Ninety percent of tumors were localized in the femur or the tibia.

RESULTS

Fifteen percent of our patients experienced a graft-related failure. The major complications were nonunion (40%), fracture (29%), and infection (14%). Complications occurred in 76% of patients and reoperations were necessary in 70% of patients. The median time to the latest complication was thirty-two months (range, zero to 200 months). The median time to full weight-bearing was nine months (range, one to eighty months). Fifteen grafts failed, twelve of which failed in the first four years. None of the thirty-four tibial reconstructions failed. Reconstruction site, patient age, allograft length, nail-only fixation, and non-bridging osteosynthesis were the most important risk factors for complications. Adjuvant chemotherapy and irradiation had no effects on complication rates.

CONCLUSIONS

We report high complication rates and considerable failure rates for the use of intercalary allografts; complications primarily occurred in the first years after surgery, but some occurred much later after surgery. To reduce the number of failures, we recommend reconsidering the use of allografts for reconstructions of defects that are ≥15 cm, especially in older patients, and applying bridging osteosynthesis with use of plate fixation.

Role of surgical margin on local recurrence in high risk extremity osteosarcoma: a case-controlled study

BACKGROUND

The relationship between surgical margin and local recurrence (LR) in osteosarcoma patients with poor responses to chemotherapy is unclear. Moreover, the incidences of LR according to three different resection planes (bone, soft tissue, and perineurovascular) are not commonly known.

METHODS

We evaluated the incidence of LR in three areas. To assess whether there is a role of surgical margin on LR in patients resistant to preoperative chemotherapy, we designed a case (35 patients with LR) and control (70 patients without LR) study. Controls were matched for age, location, initial tumor volume, and tumor volume change during preoperative chemotherapy.

RESULTS

LR occurred at the soft tissues in 18 cases (51.4%), at the perineurovascular tissues in 11 cases (31.4%), and at the bones in six cases (17.2%). The proportion of inadequate perineurovascular margin was higher in the case group than in the control group (p = 0.01). Within case-control group (105 patients), a correlation between each margin status and LR at corresponding area was found in the bone (p < 0.001) and perineurovascular area (p = 0.001).

CONCLUSIONS

LR is most common in soft tissues. In patients showing similar unfavorable responses to chemotherapy, the losses of perineurovascular fat plane on preoperative magnetic resonance imaging may be a valuable finding in predicting LR.

Intercalary reconstructions with vascularised fibula and allograft after tumour resection in the lower limb

Reconstruction with massive bone allograft and autologous vascularised fibula combines the structural strength of the allograft and the advantages of fibula's intrinsic blood supply. We retrospectively analysed the outcome of twelve patients (4 male, 8 female) who received reconstruction with massive bone allograft and autologous vascularised fibula after tumour resection in lower limb. Mean age was 17.8 years (range 11–31 years), with following primaries: Ewing's sarcoma (n = 6), osteosarcoma (n = 4), liposarcoma grade 2 (n = 1), and adamantinoma (n = 1). Mean followup was 38.7 months (median 25.7 months; range 2–88 months). Seven tumours were located in the femur and five in the tibia. The mean length of bone defect was 18.7 cm (range 15–25 cm). None of the grafts had to be removed, but there occurred four fractures, four nonunions, and two infections. Two patients developed donor side complication, in form of flexion deformity of the big toe. The event-free survival rate was 51% at two-year followup and 39% at three- and five-year followup. As the complications were manageable, and full weight bearing was achieved in all cases, we consider the combination of massive bone allograft and autologous vascularised fibula a stable and durable reconstruction method of the diaphysis of the lower limbs.

Joint-preserving tumor resection and reconstruction using image-guided computer navigation

BACKGROUND

Joint-preserving surgery is performed in select patients with bone sarcomas of extremities and allows patients to retain the native joint with better joint function. However, recurrences may relate to achieving adequate margins and there is frequently little room for error in tumors close to the joint surface. Further, the tumor margin on preoperative CT and/or MR images is difficult to transpose to the actual extent of tumor in the bone in the operating room.

QUESTIONS/PURPOSES

We therefore determined whether joint-preserving tumor surgery could be performed accurately under image-guided computer navigation and determined local recurrences, function, and complications.

METHODS

We retrospectively studied eight patients with bone sarcoma of extremities treated surgically by navigation with fused CT-MR images. We assessed the accuracy of resection in six patients by comparing the cross sections at the resection plane with complementary prosthesis templates. Mean age was 17 years (range, 6-46 years). Minimum followup was 25 months (mean, 41 months; range, 25-60 months).

RESULTS

The achieved resection was accurate, with a difference of 2 mm or less in any dimension compared to that planned in patients with custom prostheses. We noted no local recurrence at latest followup. The mean Musculoskeletal Tumor Society score was 29 (range, 28-30). There were no complications related to navigation planning and procedures. There was no failure of fixation at the remaining epiphysis.

CONCLUSIONS

In selected patients, the computer-assisted approach facilitates precise planning and execution of joint-preserving tumor resection and reconstruction. Further followup assessment in a larger study population is required in these patients.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Instructions for Authors for a complete description of levels of evidence.

Evaluation of long-term outcomes of pasteurized autografts in limb salvage surgeries for bone and soft tissue sarcomas

BACKGROUND

Pasteurized autografts used in limb salvage operations for malignant musculoskeletal tumors have several advantages, including reduced disease transmission, economic efficiency, accessibility, and anatomical conformation. However, their use has been associated with bone absorption, fracture, and pseudarthrosis. Few studies exist which have assessed the long-term outcomes of pasteurized autografts. The purpose of this study was to investigate the clinical outcomes of patients treated with pasteurized autografts and to compare these outcomes across various graft types.

METHODS

A retrospective analysis of 46 patients treated with pasteurized autografts between 1992 and 2010 was conducted. The analysis included 22 intercalary bone grafts, 17 inlay grafts, 4 composite grafts, and 3 osteochondral grafts, with the mean follow-up period of 8.7 years (2-17 years).

RESULTS

The 10-year survival rate of the 46 pasteurized autograft cases analyzed was 93.5 %, and the average bone union time between host and pasteurized autogenous bone was 9.5 months. Infections were identified in 6 (13 %) patients, fractures in 7 (15 %) patients, non-union in 8 (17 %) patients, and bone absorption in 6 (13 %) patients. Inlay grafts were completely incorporated with the host bone at the follow-up period. Combination with a vascularized fibular graft significantly reduced the risk of non-union and bone absorption (p < 0.05 and p < 0.01, respectively), with an average functional score of 23.1/30 (83.8 %).

CONCLUSION

Our findings show that pasteurized bone grafts in combination with vascularized fibular grafts have improved outcomes and potential clinical indications.

Factors affecting outcome of massive intercalary bone allografts in the treatment of tumours of the femur

We retrospectively reviewed 101 consecutive patients with 114 femoral tumours treated by massive bone allograft at our institution between 1986 and 2005. There were 49 females and 52 males with a mean age of 20 years (4 to 74). At a median follow-up of 9.3 years (2 to 19.8), 36 reconstructions (31.5%) had failed. The allograft itself failed in 27 reconstructions (24%).

Mechanical complications such as delayed union, fracture and failure of fixation were studied. The most adverse factor on the outcome was the use of intramedullary nails, followed by post-operative chemotherapy, resection length > 17 cm and age > 18 years at the time of intervention. The simultaneous use of a vascularised fibular graft to protect the allograft from mechanical complications improved the outcome, but the use of intramedullary cementing was not as successful.

In order to improve the strength of the reconstruction and to advance the biology of host–graft integration, we suggest avoiding the use of intramedullary nails and titanium plates, but instead using stainless steel plates, as these gave better results. The use of a supplementary vascularised fibular graft should be strongly considered in adult patients with resection > 17 cm and in those who require post-operative chemotherapy.

Femoral loads during gait in a patient with massive skeletal reconstruction

BACKGROUND

Biological massive skeletal reconstructions in tumours adopt a long rehabilitation protocol aimed at minimising the fracture risk. To improve rehabilitation and surgical procedures it is important to fully understand the biomechanics of the reconstructed limb. The aim of the present study was to develop a subject-specific musculoskeletal model of a patient with a massive biological skeletal reconstruction, to investigate the loads acting on the femur during gait, once the rehabilitation protocol was completed.

METHODS

A personalised musculoskeletal model of the patient's lower limbs was built from a CT exam and registered with the kinematics recorded in a gait analysis session. Predicted activations for major muscles were compared to EMG signals to assess the model's predictive accuracy.

FINDINGS

Gait kinematics showed only minor discrepancies between the two legs and was compatible with normality data. External moments showed slightly higher differences and were almost always lower on the operated leg exhibiting a lower variability. In the beginning of the stance phase, the joint moments were, conversely, higher on the operated side and showed a higher variability. This pattern was reflected and amplified on the femoral forces where the differences became important: on the hip, a maximum difference of 1.6 BW was predicted. The variability of the forces seemed, generally, lower on the operated leg than on the contralateral one.

INTERPRETATION

Small asymmetries in kinematic patterns might be associated, in massive skeletal reconstruction, to significant difference in the skeletal loads (up to 1.6 BW for the hip joint reaction) during gait.

Total condylar unipolar expandable prosthesis for proximal tibia malignant bone tumors in early childhood

Wide resection and reconstruction of tumors of the proximal tibia in the pediatric population are challenging procedures. The use of hinged, expandable prostheses may cause early closure of the distal femoral growth plate, which may increase the risk of limb discrepancy already present in this population. Between 1991 and 2001, 2 girls and 1 boy, aged 6, 6, and 4 years, respectively, were diagnosed with osteosarcoma of the proximal tibia and treated with wide resection and reconstruction with a condylar unipolar expandable tibial prosthesis. A press-fitted technique was used for component insertion. All patients received neoadjuvant and adjuvant chemotherapy. Radiographic and functional follow-up took place at least once a year for a minimum of 4 years. Adequate pain control, limb-length equality, and acceptable function were obtained in all patients. One patient presented with significant range of motion reduction (0°- 30°) in the affected knee. Limb lengthening was performed as needed to maintain balanced limb length. All patients had a good Musculoskeletal Tumor Society category score. No complications occurred in terms of component loosening or infection. One patient died shortly after 4-year follow-up because of doxorubicin-induced leukemia. Currently used hinged, expandable prostheses can jeopardize the unaffected distal femoral growth plate. This article describes a technique of reconstruction that spares the distal femoral growth plate. Adequate limb length can be expected with acceptable functional outcome. However, it is imperative to keep in perspective the expectations of the physician, the physician's team, the patient, and the patient's family.

Intercalary diaphyseal endoprosthetic reconstruction for malignant tibial bone tumours

The best method of reconstruction after resection of malignant tumours of the tibial diaphysis is unknown. In the absence of any long-term studies analysing the results of intercalary endoprosthetic replacement, we present a retrospective review of 18 patients who underwent limb salvage using a tibial diaphyseal endoprosthetic replacement following excision of a malignant bone tumour. There were ten men and eight women with a mean age of 42.5 years (16 to 76). Mean follow-up was 58.5 months (20 to 141) for all patients and 69.3 months (20 to 141) for the 12 patients still alive. Cumulative patient survival was 59% (95% confidence interval (CI) 32 to 84) at five years. Implant survival was 63% (95% CI 35 to 90) at ten years. Four patients required revision to a proximal tibial replacement at a mean follow-up of 29 months (10 to 54). Complications included metastases in five patients, aseptic loosening in four, peri-prosthetic fracture in two, infection in one and local recurrence in one. The mean Musculoskeletal Tumor Society score and the mean Toronto Extremity Salvage Score were 23 (17 to 28) and 74% (53 to 91), respectively.

Although rates of complication and revision were high, custom-made tibial diaphyseal replacement following resection of malignant bone tumours enables early return to function and provides an attractive alternative to other surgical options, without apparent compromise of patient survival.

Healing of long-term frozen orthotopic bone allografts is not affected by MHC differences between donor and recipient

BACKGROUND

The use of bone grafting in orthopaedic surgery has increased dramatically in recent years. However, the degree to which immune responses are important for the survival of the allograft is not fully understood. In particular it remains unclear whether differences in the major histocompatibility complex (MHC) influence incorporation of bone allografts and their subsequent biologic performance.

QUESTIONS/PURPOSES

Therefore, we asked whether isolated mismatch for MHC antigens of deep frozen bone allografts in the long-term causes (1) immune reactions, and whether these reactions have any effect on (2) morphologic features of the graft, (3) radiographic graft healing, and (4) graft strength.

METHODS

We used an established orthotopic tibial segment transplantation technique that allows determination of mechanical strength, histologic evaluation, and immune responses. Tibial segments that had been deep-frozen at -80°C for 1 year were transplanted into 24 PVG (RT1 (c)) rats from either 12 syngeneic donors or 12 MHC congenic donors PVG.1U (RT1 (u)). We determined immune responses using an indirect Coombs reaction and determined graft healing radiographically and mechanically after 6 months.

RESULTS

We detected no alloantibody production to graft MHC-I antigens, and found no differences between syngeneic and MHC mismatched grafts in terms of remodeling with host bone, graft healing, and mechanical strength.

CONCLUSIONS

Mismatches for MHC antigens do not seem to play a decisive role in healing of long-term, deep-frozen bone allografts.

Outcome of the intramedullary diaphyseal segmental defect fixation system for bone tumors

BACKGROUND

Resection of diaphyseal malignant bone tumors is indicated for local control and impending pathological fracture or failure of prophylactic internal fixation. However, there are no large, long-term studies analyzing the results of intercalary reconstruction using segmental metallic spacers.

MATERIALS AND METHODS

We present 24 patients treated with wide resection for primary or metastatic bone tumors involving the diaphysis of the femur, tibia, or humerus and reconstruction using a modular intramedullary diaphyseal segmental defect fixation system. The mean length of bone resection was 10 cm. The postoperative complications and outcome were evaluated.

RESULTS

At a mean follow-up of 29 months, 17 patients were alive and 7 patients were dead of disease; no patient had local recurrence. Implant-related complications occurred in 8 patients, the most common being mechanical loosening and rotational instability. Loosening was most common in reconstructions of more than 10 cm length of bone resection. In all femoral reconstructions, mechanical failure occurred at the proximal stem. True limb length discrepancy of 2.0 cm was observed in one patient. Wound healing complications were not observed; range of motion and function of the adjacent joints was within normal limits.

CONCLUSIONS

The modularity, ease of application and preservation of the adjacent joints are major advantages of segmental modular prostheses; however, the complications' rate is high. Complications occur most often at the proximal stem in femoral reconstructions and reconstructions for more than 10 cm length of bone resection. In these cases, the use of these implants should be reconsidered or not recommended.

No effect of dynamic loading on bone graft healing in femoral segmental defect reconstructions in the goat

We studied if a static or dynamic mode of nail fixation influenced the healing of segmental defect reconstructions in long bones. Defects in the femur of goats were reconstructed using a cage filled with firmly impacted morsellised allograft mixed with a hydroxyapatite paste (Ostim). All reconstructions were stabilised with an intramedullary nail. In one group (n=6) the intramedullary nail was statically locked, in the second group (n=6) a dynamic mode of nail fixation was applied. We hypothesised that dynamisation of the nail would load, and by that stimulate the healing of the bone graft. Mechanical torsion strength of the reconstructions of the femur with the static and dynamic mode of nail fixation appeared to be 74.8±17.5% and 73.0±13.4%, respectively as compared with the contralateral femurs after 6 months. In all reconstructions, the grafts united radiographically and histologically to the host bone, and remodelled into a new vital bone structure. No large differences were found between newly formed bone areas inside and outside the mesh of the two groups. The area of callus outside the mesh in the dynamic mode of fixation group was smaller (p=0.042), whilst the percentage of bone outside the mesh was larger (p=0.049), as compared to the static mode of fixation group. The data suggest that healing of these defects with impacted morsellised graft in a cage is not significantly influenced by the mode of fixation of the nail in this model.

Joint-sparing or physeal-sparing diaphyseal resections: the challenge of holding small fragments

BACKGROUND

Joint-sparing or physeal-sparing diaphyseal resections are technically challenging when only a small length of bone is available for implant purchase.

QUESTIONS/PURPOSES

We describe a series of cases with the aim of generating some guidelines as to the choice of reconstruction method and the implant used.

METHODS

We retrospectively reviewed 25 patients with diaphyseal resections in which the remaining epiphyseal or metaphyseal segment provided 3 cm or less of purchase. Reconstruction was performed with bone (allograft, extracorporeally radiated autograft, or vascularized fibula) in 19 cases or a custom diaphyseal implant (CDI) in six. The implants used for holding the bone construct varied from standard plates to custom plates. The presence of union, function, complications, and disease status at last followup was recorded.

RESULTS

Sixteen of the 25 patients are disease-free and alive with the original construct at a median followup of 34 months (range, 12-66 months). Implant-related complications such as plate breakage (four) and angulation (three) happened more frequently when weak plates such as reconstruction plates were used. Local recurrence with pulmonary metastases occurred in two cases. The two deep infections required an amputation or rotationplasty for control. Custom plates were successful in three of four patients.

CONCLUSIONS

Weak plates such as reconstruction plates are best avoided for these reconstructions. Custom plates allow secure fixation with technical ease. CDIs allow immediate weightbearing and ability to lengthen with predictable good functional short-term outcome.

Stringent patient selection in bulk allograft reconstructions

We hypothesized that stringent patient selection in the use of large bulk structural allografts for limb preservation would positively affect outcomes and decrease complication rates by eliminating certain comorbid or social factors known to contribute to the most detrimental sources of allograft failure: infection, fracture, and nonunion.Our selection criteria included patients who were younger than 50 years, nonsmokers, non-obese (body mass index <40), who did not receive radiation therapy to the recipient site perioperatively, and who underwent intercalary allograft reconstruction except in the upper extremity where osteoarticular allografts were permitted. Outcomes were assessed using the Musculoskeletal Tumor Society (MSTS) and Toronto Extremity Salvage Score (TESS) scoring systems. Twenty-three patients fulfilled our cohort inclusion criteria. The overall survival rate for the 23 allografts was 91% (21/23). Average MSTS and TESS scores were 76% and 87%, respectively. Eleven of 23 patients experienced at least 1 complication requiring a second procedure. Musculoskeletal Tumor Society scores among patients experiencing no complications averaged 83% vs 71% for patients experiencing at least 1 complication. Average TESS scores were 89% and 86%, respectively.The results of our early experience indicate there is no appreciable difference in complication rates among our series of patients stringently selected for bulk allograft reconstruction compared to other previously reported studies.

Adamantinoma of the tibia treated with a new intramedullary diaphyseal segmental defect implant

In this case report, a 75-year old male presented with a mass on the anterior surface of the mid-shaft of the right tibia. Imaging studies showed a well-circumscribed radiolucent lesion in the anterior tibial cortex, without soft tissue extension. Plain radiographs and computed tomography scan of the chest were negative. Histological diagnosis was consistent with adamantinoma, a rare primary bone tumour. Wide tumour resection of approximately 16 cm of the tibial diaphysis with a surrounding cuff of normal tissue was performed. The bone defect was reconstructed using an intramedullary diaphyseal segmental defect fixation system. At 26 months post-operatively the patient is alive with no evidence of local recurrence, distant metastases or implant failure. The intramedullary diaphyseal segmental defect fixation system is associated with excellent oncological and functional outcomes. Intra-operative modularity, ease of application, immediate post-operative stability and rapid rehabilitation are the major advantages of this diaphyseal prosthesis.

Biological reconstruction after resection of bone tumours around the knee

We reviewed 25 patients who had undergone resection of a primary bone sarcoma which extended to within 5 cm of the knee with reconstruction by a combination of a free vascularised fibular graft and a massive allograft bone shell. The distal femur was affected in four patients and the proximal tibia in 21. Their mean age at the time of operation was 19.7 years (5 to 52) and the mean follow-up period 140 months (28 to 213). Three vascularised transfers failed. The mean time to union of the fibula was 5.6 months (3 to 10) and of the allograft 19.6 months (10 to 34). Full weight-bearing was allowed at a mean of 21.4 months (14 to 36). The mean functional score at final follow-up was 27.4 (18 to 30) using a modfied 30-point Musculoskeletal Tumour Society rating system. The overall limb-salvage rate was 88%. The results of our study suggest that the combined use of a vascularised fibular graft and allograft is of value as a limb-salvage procedure for intercalary reconstruction after resection of bone tumours around the knee, especially in skeletally immature patients.

The stability of impacted morsellized bone grafts in a metal cage under dynamic loaded conditions: an in vitro reconstruction of a segmental diaphyseal bone defect

INTRODUCTION

Reconstructions of segmental diaphyseal bone defects with massive allografts are related to complications like nonunion and fractures. A reconstruction of these defects with a cage filled with an impacted morsellized bone graft could be an alternative. The bone graft in these cages should ideally be loaded to prevent resorption. Loading of morsellized bone grafts however can cause instability. The goal of this study was to assess the stability of an impacted morsellized bone graft in a cage under dynamic loaded conditions in an in vitro reconstruction of a segmental diaphyseal bone defect. The second goal was to assess the influence of cage type, washing of the graft and bone-cage fit.

MATERIALS AND METHODS

Two different cage types were filled with impacted morsellized bone graft. The grafts were used washed and unwashed and in variable bone-cage fit conditions. We recorded the bone graft deformation in the cage under dynamic loaded conditions.

RESULTS

Stability appeared to be not very sensitive to the cage type and whether the bone chips were washed or not. However, quality of the fit of the cage with the bone segment was an important parameter and should be optimized during surgery.

CONCLUSIONS

Morsellized impacted bone graft in a cage is stable in dynamic loaded conditions in an in vitro reconstruction of a segmental diaphyseal bone defect. We believe that this method of reconstruction is a promising alternative for the reconstruction of large diaphyseal bone defects and should be tested relative to its biological merits in animal experiments.

Is an impacted morselized graft in a cage an alternative for reconstructing segmental diaphyseal defects?

Large diaphyseal bone defects often are reconstructed with large structural allografts but these are prone to major complications. We therefore asked whether impacted morselized bone graft could be an alternative for a massive structural graft in reconstructing large diaphyseal bone defects. Defects in the femora of goats were reconstructed using a cage filled with firmly impacted morselized allograft or with a structural cortical autograft (n = 6 in both groups). All reconstructions were stabilized with an intramedullary nail. The goats were allowed full weightbearing. In all reconstructions, the grafts united radiographically. Mechanical torsion strength of the femur with the cage and structural cortical graft reconstructions were 66.6% and 60.3%, respectively, as compared with the contralateral femurs after 6 months. Histologically, the impacted morselized graft was replaced completely by new viable bone. In the structural graft group, a mixture of new and necrotic bone was present. Incorporation of the impacted graft into new viable bone suggests this type of reconstruction may be safer than reconstruction with a structural graft in which creeping substitution results in a mixture of viable and necrotic bone that can fracture. The data suggest that a cage filled with a loaded morselized graft could be an alternative for the massive cortical graft in reconstruction of large diaphyseal defects in an animal model.

Surgical management of primary osteosarcoma

Surgical strategies for the primary tumor for patients with extremity and pelvis osteosarcoma have evolved from the ablative to limb-sparing approaches over the past three decades. Favorable oncologic and functional outcomes with contemporary tissue-conserving techniques consistently observed in skeletally mature patients have prompted the application of similar approaches to a growing number of eligible skeletally immature patients. In response to emerging long-term outcome data, current strategies have focused principally on refining the nature and scope of surgical resection to preserve uninvolved tissues, and on the adoption of novel biological and nonbiological skeletal and soft-tissue reconstruction methods to optimize function. We focus on these clinical issues and discuss current efforts to advance the surgical management of the primary tumor and address the limitations of the definitive treatment of the primary tumor, including locally recurrent disease and complications of skeletal reconstructions.

Survival of massive allografts in segmental oncological bone defect reconstructions

Reconstructions of large segmental bone defects after resection of bone tumours with massive structural allografts have a high number of reported complications including fracture, infection and non-union. Our goal is to report the survival and complications of massive allografts in our patients. A total of 32 patients were evaluated for fracture, infection, non-union rate and survival of their massive allograft reconstructions. The average follow-up for this group was five years and three months. The total fracture rate was 13% with a total infection rate of 16%. We found a low union rate of 25%. The total survival of the allografts was 80.8% (+/- 18.7%) after five years. We found a five-year allograft survival of 80.8% which is comparable with other studies.

Free vascularized fibular graft salvage of complications of long-bone allograft after tumor reconstruction

BACKGROUND

Long-bone allograft reconstruction following tumor extirpation can be complicated by problems such as nonunion at the host-allograft junction, allograft fracture, or allograft infection. Free vascularized bone grafts can be used to address these complications. The purpose of the current study was to examine retrospectively the outcomes and complications following allograft reconstruction salvage with onlay vascularized fibular grafts.

METHODS

A tumor registry review was conducted to identify all patients who underwent a reconstruction with a vascularized fibular graft for allograft reconstruction complications following tumor resection (host-graft nonunion, allograft fracture, or allograft nonunion) in the last nineteen years. The records of these patients were analyzed for details regarding the neoplasms and the treatment thereof, details of the free vascularized fibular graft reconstruction, time to osseous union, functional outcome, and clinical outcome.

RESULTS

Thirty-three patients satisfied the criteria for this study. The involved bones were the femur (eighteen patients), tibia (eight), and humerus (seven). Osseous union was achieved in all patients at a mean of 7.7 months. The average duration of follow-up was seventy-three months. Twenty-three patients achieved a good or excellent functional outcome. Ultimately, seven patients had a failure of the allograft reconstruction, which resulted in limb loss in five of them. Postoperative complications were relatively common in this series.

CONCLUSIONS

Free vascularized fibular grafting is a useful adjunctive surgical treatment for nonunion, fracture, and infection of an intercalary allograft reconstruction in limb salvage surgery. It has, however, a high rate of associated complications often resulting in failure.